Method of and apparatus for promoting combustion



3 SheetQ-Sheet 1. B. P. TAYLOR. METHOD OF AND APPARATUS FOR PROMOTINGCOMBUSTION.

Patented Sept. 10,1895.

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'B. F. TAYLOR. METHOD OF AND APPARATUS FOR PROMOTING COMBUSTION.

No. 546,259. Patented Sept. 10, 1895.

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B.'F.TAYLOR. METHOD OI AND APPARATUS FOR PROMOTING COMBUSTION. No.545,259. Patented Sept. 10, 1895.

Attest: I Inventor. %M M fla W UNITED STATES PATENT Enron.

BENJAMIN F. TAYLOR, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE TAYLORIMPROVED DRAUGHT COMPANY, OF NEYV JERSEY.

METHOD OF AND APPARATUS FOR PROMOTING COMBUSTION.

SPECIFICATION forming part of Letters Patent No. 546,259, datedSeptember 10, 1895.

Application filed March 30, l 895.

To ctZZ whom it may concern.-

Be it known that I, BENJAMIN F. TAYLOR. a citizen of the United States,residing in the city of Newark, county of Essex, and State of NewJersey, have invented a new, useful, and Improved Method of andApparatus for Promoting Combustion, 850.; and I do hereby declare thatthe following is a full, clear, and exact description of the invention,which will enable others skilled in the art to which it pertains to makeand use the same.

That part of my invention which constitutes a method relates to thecombustion of fuel, and its object is to insure the oxidation of thecombustible'gases, which, as is well known, constantly escape from thecombustion-chambers of all furnaces without being consumed.

The structural features of my invention relate to furnaces, my aimhaving been to produce not merely an apparatus for performing theaforesaid method, but a simple and inexpensive device which may beapplied to existing furnaces without changing their structures, andwhich will, when thus applied, cause these furnaces to operate inaccordance with the principles of my invention.

The method, generally stated, consists in removing the products ofcombustion so as to relieve gases which are within the region ofignit'erous temperatures of the weight of said products, and insupplying to the combustible elements a measured or restricted supply ofair.

The apparatus, in its broad aspect, consists of a natural-draft furnaceprovided with a suitable air-feeder situated at some proper pointbetween the combustion-chamber and the top of the stack and adapted toforce the escaping gases upward, so as to maintain a good draft evenwhen the ash-pit doors are partially closed.

It is a well-known fact that it the draftdoors are open far enough topermit atmospherio pressure to have its full or a proper effect upon themobile matter within a furnace, excessive quantities of air will besupplied to the comhustion'chamber; and that, on the other hand, if thesaid doors are so nearly closed that they will admit, at normalvelocity, just the quantity of air that is Serial No. 543,812. (Nomodel.)

needed for the purposes of combustion, the effect of atmosphericpressure and the conse quent velocity of the air-current will be sogreatly reduced that it will be impossible to I maintain an adequatesupply of air.

Atmospheric pressure is capable of doing a. certain and fixed amount ofwork when permitted to exert itself in the direction of a place of givenlow pressure, and the work done, when considered with reference to agiven quantity of air flowing to the place of low pressure, produces amaximum velocity in such current when there are no interposed obstaclesto retard the flow. The size of an air-opening determines the factor ofretardation, while the pressure within the air-opening varies theresistance. A lowering of the resistance effectuatcs a higher velocityand an increased flow of the air-current, because atmospheric pressurehas then less work to do in forcing a given quantity of air through theopening. I propose for this reason to lessen the work to be donebyatmospheric pressure at the draft-doors of a furnace, and this Iaccomplish by applying atmospheric pressure to the mobile matter atanother point of the apparatus, so that the heavy gases beyond thecombustion-ch amber will be lifted out of the stack and thus exertlittle or no downward pressure upon the gases within thecombustion-chamber. By pursuing this plan I am enabled to so regulatethe supply of air to the combustion-chamber that excessive quantities ofoxygen and nitrogen do not have to be heated by the igneous fuel.

The details of the invention are hereinafter fully described, andclearly pointed out in the claims.

Referring to the drawings, which illustrate the apparatus, Figure 1 is aplan view of a furnace and stack with one form of my attachment inposition. Fig. 2 is a vertical sec tional View of the same furnace, onthe line y y, Fig. 1. Fig. 3 is a vertical sectional view of one form ofmy air-supplying device. Fig. 4 is a perspective view of one form ofdamper or slide to be used in connection with the device. Fig. 5 is avertical sectional view of a stack with a modified form of air-supplyingdevice attached thereto. Fig. 6 is a plan view of the stack andair-supplying device shown in Fig. 5. Fig. 7 is a face view of theair-supplying device detached and enlarged. Fig. 8 is a side View of thedevice shown in Figs. 5 to 7. Fig. 9 is a sectional view of a stack withstill another form of air-supplying device in position. Fig. 10 is aperspective view of the attachment shown in Fig. 9. Fig. 11 is a planview of the attachment shown in the two preceding figures; and Fig. 12is a plan view of the stack shown in Fig. 9, with three of theattachments in position.

Referring to Figs. 1 to 4, inclusive, the character A designates anordinary return-flue boiler provided with the usual fines A and G. F isa breeching connecting the tines A and G. B designates the front of thefurnace, which is provided with the ordinary fuel-door C and ash-pitdoor E. D designates the grate within the furnace upon which issupported the fuel J. K represents the bridgewall usually found in suchfurnaces. H designates a stack with which the flue G connects. Openingsare arranged in the side of this stack for the introduction of myair-supplying devices.

Referring in detail to that form of air-supplying device shown in Fig.3, I represents the structure as an entirety. It is composed of a tubeCL and a tube Cb, so arranged as to form a continuous channel, the tubea communieating with the atmosphere and thereby forming a channel 6. Aplate I) is arranged to slide over the end of the tube a, so as toregulate the size of the passage 6 and thereby control the amount of airflowing through .the feeder. A tube 0 is arranged inside of the tube aand is provided with an opening Z) in its bottom, thus formingcommunication with the interior of the stack, so that a certain amountof the products of combustion will pass up through such tube. The tubecshould terminate below the top of the tube Ct, whereby a chamber isformed wherein those portions of the furnace-gases which enter the holeI) are mixed with the atmospheric air which flows into the tube throughthe passage 6 in the side of the stack. These devices may be modifiedmore or less in form, and two additional forms are illustrated herein,namely: that shown in Figs. 5 to 8, inclusive, and that shown in Figs. 9to 12, inclusive. Referring to the figures which illustrate the first ofthese two modifications, S, in Fig 5, designates a stack of ordinaryconstruction to which the attachment 1 is applied. The same referencecharacters are used in these figures to designate parts corresponding tothose shown in Fig. 3. a designates the tube communicating with theatmosphere, and a the vertical tube communicating therewith and arrangedon the interior of the stack. crepresents the smaller internal tubecommunicating with the stack and discharging into the tube a, thusforming an opening I) for the products of combustion to pass through. Aflange d is provided to rest against the outer surface of the chimney,by which the attachment may be secured in position, as by bolts g, shownin Fig. 6. A tubular shield or nozzle e is arranged to extend from theflange (1 into the pipe at, nearly to the side of the tube 0. Holesfarearranged in the outer end of thenozzle e to admit air between the nozzleand pipe a.

In Figs 9 to 12, inclusive, S designates a stack of ordinaryconstruction, and 1" the attachment applied thereto. In thismodification the character a designates ashort horizontal pipe openinginto the outer air and communicating with a bulb 2', arranged within thestack. To this bulb t'is attached a tube ct, open at both endsand thusforming communication between the bulb and the interior of the stack.The bottom of the bulb is perforated, and a tube 0 is arranged thereinand extends up into the tube a and nearly to the top thereof, forming anopening Z2 for the products of combustion to pass therethrough. In thismodification, also, d represents a flange arranged on the exterior ofthe stack, by means of which the air-supplying device is secured inposition.

The action of each of the air-supplying devices which I have shown anddescribed is like that of an injector. The atmospheric pressure outsideof the stack is greater than the pressure of the rarified gases withinthe stack, and the outer air has, therefore, a preponderating forcewhich compels it to seek the interior of the stack in the form of acurrent of considerable velocity, which current by inductive actionentrains certain portions of the gases within the stack and forces themto leave the stack through the outlet at the top thereof. The inductiveaction is enhaneed by the presence of the pipe 0 in each one of theseveral air-supplying devices. This pipe 0, being in each instanceshorter than the pipe a, which constitutes the discharge-end of each ofthe air-supplying devices, there is a mixture of air and products ofcombustion in the said discharge end. The effect of this mixture is toprevent the air-current from continuing as a distinct current andescaping from the stack without doing the work of removing products ofcombustion. Of course certain portions of the products outside of theair -supplying device are entrained by the mixed current of air andproducts just referred to, and in this way there is produced anadditional effect in respect to the removal of products of combustionfrom the top of the stack. The prime function of the air-supplyingdevices will thus be seen to be the removal of products of combustionfrom the upper portion of the stack, whereby there is alessening of thework, which in furnaces of ordinary character has to be whollyaccomplished by atmospheric pressure exerted through ash-pit doors orother and equivalent feed-openings for air-that is to say, theair-supplying devices, considered in their broadest aspect, are meansfor lifting out of the stack the upper portions of the gases therein;and, since a portion of the column of sult will be an increase in thequantity of air admitted to the combustion-chamber; but an increasedquantity of air is not desired, because an excessive quantity ofnitrogen and oxygen means an increase in the quantity of heat-unitsabsorbed by these gases and wasted by being carried from the apparatusthrough the stack. In order to obviate this difficulty the ash-pit doorsor other feed-openings for air are closed to a considerable extent, sothat the quantity of air supplied to the combustion-chamber at the newor higher velocity will be restricted to the amount which will give tothe combustible elements the approximate or exact number of atoms ofoxygen which combustion demands. This result cannot be accomplishedwhere all the atmospheric pressure which causes the flow of gasesthrough the furnace and stack is applied at the ash-pit doors, it beingtrue, as experience has demonstrated to those who are familiar with theoperation of furnaces, that the ashpit doors of ordinary furnaces cannotbe regulated so as to admit just the volume of air required for purposesof combustion and at the same time permit the action of atmosphericpressure that will effectuate a proper flow of products from theapparatus.

The ash-pit doors may, when my devices are in operation, be regarded asmeans for measuring the air which is used for the purposes ofcombustion, because the ash-pit openings are at such time deprived oftheir usual and principal function of permitting at1nospheric pressureto move the column of gases in accordance with the well-known method ofproducing draft.

As above indicated, the furnace is of a very ordinary construction. Ihave made no change therein except to add the air supplying and forcingdevices just referred to, and yet it has been demonstrated in practiceand by scien tifically conducted experiments that this simple additionproduces a surprising economy of fuel.

The air-feeding devicesmust be situated so far away from the furnacethat they will not operate to produce secondary combustion. The bestresults have been attained by placing the devices in a staggeringposition, from two to three feet one above the other, and at an averageheight of a little less than onethird the distance between the uptakeand the top of the stack, so that they will not impair the velocity ofthe upward-going column. The amount of air to be admitted to the chimneyvaries with the heat of the escaping gases CAD and with the velocitywith which they ascend, as'well as according to the difference in the.

kinds of coal used, since I have found that the draft-pressu re variesaccording to the differences in chemical composition of the coals asWell as according to the degree of heat with which the escaping gasesmake their exit from the furnace. The pressure within thecombustion-chamber being lessened by'the lifting of the upper portion ofthe column of escap inggases, diffusion of the air and combustible gaseswithin the furnace is enhanced and a betterand more economicalcombustion thereby obtained, it being a well-known law that gasesdifiuse more rapidly under low than under high pressures.

The operation of my invention can perhaps be explained by giving anillustration. Take a plant. with a chimney ninety feet in height, closethe ash-pit doors, and the ascending column of escaping gases leavingthe furnace moves very slowly, and if the ash-pit doors are left closedlong enough the fire will die down. Now, insert the device in the mannerheretofore described. Immediately the necessary supply of air will beconveyed into the chimney, and the in jector-like action or spiralmotion produced in the column of air above the air-feeder will act likea suction on that portion of the escaping gases below the airfeeder andon the fire in the furnace. The ash-pit doors, being further closedduring this operation, the gases formed by the distillation of the fuelwill be consumed before they can be carried away. The chimney propervirtually terminates just below the the air-inlets and the portionabove, including the air-inlets or devices, unites and may be consideredas an appliance for removing products of combustion by suction.

Having thus fully described my invention, what I claim, and desire tosecure by Letters Patent, is

1. The method of promoting combustion which consists in removingproducts of combustion so as to relieve gases which are within theregion of igniferous temperatures of the weight of said products, and insupplying to the combustible elements a measured or restricted supply ofair, substantially as described.

2. The method of promoting combustion which consists in positivelyremoving products of combustion which have passed beyond the region ofigniferous temperatures, so as to relieve gases still remaining withinsaid region of the weight of said products, and in supplying to thecombustible elements a measured or restricted quantity of air,substantially as described.

3. The method of promoting combustion which consists in removingproducts of combustion which have passed beyond the region of igniferoustemperatures by means of a blast, so as to relieve gases still remainingwithin said region of the weight of said products, and in supplying tothe combustible IIO elements a measured or restricted quantity of air,substantially as described.

4. The method of promoting combustion which consists in removingproducts of combustion Which have passed beyond the region of igniferoustemperatures by means of a blast of air, so as to relieve gases stillremaining Within said region of the weight of said products, and insupplying to the combustible elements a measured or restricted quantityof air, substantially as described.

5. The method of promoting combustion which consists in removingproducts of combustion which have passed beyond the region of igniferoustemperatures by means of a blast of air produced by preponderatingatmospheric pressure, so as to relieve gases still remaining within saidregion of the Weight of said products, and in supplying to thecombustible elements a measured or restricted quantity of air,substantially as described.

6. The combination with a natural draft furnace and stack of means forlifting or removing products from the top thereof, and means forrestricting or measuring the supply of air to the combustion chamber ofthe furnace, substantially as described.

7. The combination with a natural draft furnace and stack of an injectorfor lifting or removing products from the top thereof, and means forrestricting or measuring the supply of air to the combustion chamber ofthe furnace, substantially as described.

8. The combination with a natural draft furnace and stack of anatmospheric injector for lifting or removing products from the topthereof, and means for restricting or measuring the supply of air to thecombustion chamber of the furnace, substantially as described.

9. The combination with a natural draft furnace and stack of anatmospheric injector and smoke and air mixer for lifting or removingproducts from the top thereof, and means for restricting or measuringthe supply of air to the combustion chamber of the furnace,substantially as described.

BENJAMIN F. TAYLOR.

Witnesses:

CHARLES L. BORGME-YER, THOMAS BLAKE.

